Freezer plate



Nov; 1, 1949 CAMERON 2,486,822

FREEZER PLATE Filed D80. 23. 1946.

INVENmR.

Patented Nov. 1, 1949 FREEZER PLATE Duncan L. Cameron, Detroit, Mich., assignor to George Orley, Detroit, Mich.

Application December 23, 1946, Serial No. 717,999

2 Claims.

This application relates to hollow freezer units.

The freezer unit hereon is characterized by the fact that the hollow unit, containing a coil of tubing through which refrigerant courses, is packed with a plastic mass containing a dispersion of fine metal particles for promoting heat transfer between the tubing and the walls of the unit.

An embodiment is shown in the appended drawing. In this drawing,

Fig. 1 diagrammatically illustrates a typical freezer unit and Fig. 2 is an enlarged fragmentary cross-section view on line 22 of Fig. 1.

In the appended drawing, Fig. 1 shows a freezer unit comprising two sheet metal plates l and Ill joined at their edges by the fianging of plate ll around plate l0 as illustrated at l2. Between plates l0 and II is a space within which is a coil of tubing, l4, through which refrigerant courses. Opposite ends of the tubing l4 pass through the side walls l5 of the unit, formed by the flanging of plate It, and the protruding ends of the tubing are connected by suitable couplers to a refrigerant line.

Packed into the space It between plates I0 and H. to fill all of that space except for that which is occupied by the tubing itself, is a plastic mass H in which is a dispersion of fine metal particles. The plastic is of such a nature as to remain unhardened even at temperatures below freezing. One such product is known on the market as Prestite, manufactured by Prestite Engineering Company of St. Louis, Missouri, So far as I am able to determine, this mass is of a special form of asphalt, guaranteed to remain unhardened at 40 F. In the plastic mass is a dispersion of bronze powder.

The plastic mass, packed into space It, is in intimate contact with both the tubing and the plates, and functions as a heat transfer medium between them.

The use of the plastic mass makes it unnecessary to solder or braze the tubing M to the plates l0 and Ill. Wherever the tubing is in direct and intimate contact with the plates to and H, heat transfer will take place even without the use of the plastic mass. However, since, at many points, there is an appreciable gap between the tubing and the plates, the plastic mass which fills such gaps promotes heat transfer. In addition, the plastic mass serves to equalize the distribution or heat fiow from tubing M to the plates II] and II. Such distribution is so effective, I have observed, that in units which have made, there is no frost line at the tubing but rather the frosting is spread quite evenly over the entire surface of the plates I0 and II, indicating that portions of such plates remote from the tubing are cooled by the tubing almost as effectively as portions of the plates most directly in contact with the tubing.

Now having described the hollow freezer unit herein disclosed, reference should be had to the claims which follow:

I claim:

1. A hollow freezer unit comprising two spaced metal plates joined at their edges, a coil of tubing between them, and a filling or packing for the space between said plates and around said coil, comprising an asphaltic plastic mass in which is a dispersion of fine metal particles, the plastic being unhardened even at below freezing temperatures.

2. A hollow freezer unit comprising two spaced metal plates joined at their edges, a coil of tubing between them, and a filling or packing for the space between said plates and around said coil, comprising an asphaltic plastic mass in which is a dispersion of fine metal particles, the plastic being unhardened even at below freezing temperatures, the plastic being in intimate contact with both the tubing and the plates to function as a heat transfer medium between them.

DUNCAN L. CAMERON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,932,184 Knapp Oct. 24, 1933 2,405,432 Kleist Aug. 6, 1946 2,446,895 Weiss Aug. 10, .1948 

